AB0763 CHARACTERISTICS OF RELAPSES IN EOSINOPHILIC GRANULOMATOSIS WITH POLYANGIITIS. A SINGLE CENTRE EXPERIENCE
Authors: R. Ríos-Garcés, J. Hernández-Rodríguez, S. Prieto-González, M. C. Cid, G. Espígol-Frigolé
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Eosinophilic granulomatosis with polyangiitis (EGPA) is a heterogeneous disease with a variable, relapsing course. Real-world data regarding specific characteristics of relapses in this patients are scarce. <h3>Objectives</h3> We aim to describe and analyse the relapses presented in a single-center cohort of EGPA patients. <h3>Methods</h3> Medical charts of EGPA patients regularly controlled at our department were reviewed to describe demographics, clinical characteristics at diagnosis and at relapse, number of relapses, disease activity at relapse, treatment of the relapses, damage accrual, and laboratory results. The definition of relapse was the same used in the MIRRA trial: a) active vasculitis (BVAS &gt;0), b) active asthma or active nasal or paranasal sinus disease leading either to an increase in the dose of prednisone &gt; 4mg/day, initiation of or increase in immunosuppressive therapy, or hospitalization <sup>[1]</sup>. <h3>Results</h3> A total of 59 EGPA patients were followed regularly at our department. All fulfilled either ACR 1990 and/or MIRRA trial inclusion criteria for EGPA. The mean age at diagnosis was 51.6 years, 59.3% were female and 91.5% were Caucasian. Among them, 76.3% were ANCA positive and 23.7% were ANCA negative. The mean time of follow-up was 10.7 ± 8.2 years. During the follow-up, a total of 324 relapses were diagnosed in 47 patients, with 12 patients experiencing no relapse. A relapse-free survival analysis showed that 35% of patients had a relapse in the first year, 51% at 2 years, 59% at 3 years and 64% at 5 years. The main clinical symptoms at relapse were asthma (in 248 flares, 76.5% of them), followed by rhinitis (100, 30.9%), sinusitis (60, 18.5%), skin involvement (19, 5.9%), fever (18, 5.6%), arthralgia (16, 4.9%), lung infiltrates (15, 4.6%), myalgia (12, 3.7%), peripheral nervous system involvement (11, 3.4%), cardiac involvement (6, 1.9%), arthritis (3, 0.9%), weight loss (2, 0.6%), alveolar hemorrhage (2, 0.6%), gastrointestinal involvement (2, 0.6%) and central nervous system involvement (2, 0.6%). No renal involvement was seen at flare. Median BVAS at relapse was 2 (IQR 2-4, range 0-28). When determined, median blood eosinophils at relapse were 500 cells/mm<sup>3</sup> (IQR 100-1000) and in 73% of the measures eosinophils did not reach 10% of the total leucocyte count. Median CRP was 0.6 mg/dl (IQR 0.2-2.4) and median ESR 14 mm/h (IQR 8-32). ANCA were measured in 37 relapses only, being positive in 14 of them. The median prednisone dose at relapse was 6.25mg/day and the median increase for treating the relapse was 30 mg/day. In 53 relapses, patients were already taking azathioprine. In 47, mepolizumab. In 36, methotrexate. In 11, mofetil mycophenolate. When comparing patients who relapsed vs. those who did not, and those who relapsed less than 1 time every 2 years vs those who relapsed more than 1 time every 2 years, no predictive factor of relapse was seen. <h3>Conclusion</h3> After a mean follow-up of 10.7 years, 324 relapses were diagnosed in 59 patients. First relapse occurred in 35% of patients at 1 year and in 64% at 5 years. The clinical spectrum of relapses was predominantly asthma, followed by ear, nose and throat, being vasculitic manifestations much less frequent. No predictive factors of relapse were identified. <h3>References</h3> [1]Wechsler ME et al. N Engl J Med. 2017. <h3>Acknowledgements</h3> This study was supported by Instituto de Salud Carlos III (ISCIII) through the project PI18/00461, part of Plan Estatal de Investigación Científica y Técnica y de Innovación 2013–2016, and co-funded by the European Union. Roberto Ríos-Garcés is a recipient of a Río Hortega grant from Instituto de Salud Carlos III, Spain (CM19/00032). <h3>Disclosure of Interests</h3> Roberto Ríos-Garcés: None declared, José Hernández-Rodríguez: None declared, Sergio Prieto-González: None declared, Maria C. Cid Paid instructor for: Vifor and GSK, Consultant of: GSK, Abbvie and Janssen, Grant/research support from: Kiniksa, Georgina Espígol-Frigolé Consultant of: Janssen.